US Senator Bernie Sanders has denounced the newly-approved tax overhaul bill as the “biggest act of thievery in the modern history of this country.”

On Saturday, the Senate approved the GOP tax plan that will offer huge tax cuts for US corporations and the wealthiest Americans and likely increase the budget deficit by $1 trillion in a decade, presstv.com reported.

The upper chamber of Congress voted 51 to 49 in favor of the bill, the nation's largest tax overhaul in 31 years, delivering Republicans and US President Donald Trump a major legislative victory.

Sanders described the tax rewrite as ‘class warfare,’ saying that Republicans are ‘looting the federal government’ in order to give handouts to corporations and the rich.

However, he added that the GOP will not be able to get away with the scheme.

Sanders made the remarks on Saturday in Dayton, Ohio, at an event that was part of a four-city tour against the Republican tax bill organized by progressive groups MoveOn.org and Not One Penny.

“We are winning the fight for the vision of the future of America,” the 2016 presidential candidate said. “Our vision, your vision, is gaining momentum all across this country.”

The US Senate on Saturday approved a sweeping tax overhaul.

Elsewhere in his speech, Sanders mentioned a series of Democratic victories in early November, when the party managed to pick up key state legislative seats and control of the state governments of New Jersey and Washington.

“Donald Trump’s name may not have been on the ballot,” Sanders said, “but Trumpism was on the ballot and it lost badly.”

He called on the American people to rally against the tax proposal like the response the nation gave to GOP efforts to repeal and replace Obamacare.

“What our job is to bring people together. Don’t let them divide us up by the color of our skin or where we were born or our religion. Let us stand together. Let us think big. Let us transform this country.”

Under the new bill, the corporate tax rate would be permanently slashed to 20 percent from 35 percent, while future foreign profits of US-based firms would be largely exempted from tax.